[Bug target/71009] g++: ICE on modified gdb/valarith.c with -Ofast

["egall at gwmail dot gwu.edu" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71009

--- Comment #5 from Eric Gallager <egall at gwmail dot gwu.edu> ---
I rebuilt with debugging info and got a better backtrace:

Breakpoint 1, internal_error (gmsgid=0x15ee807 "in %s, at %s:%d") at
../../gcc/diagnostic.c:1337
1337      va_start (ap, gmsgid);
(gdb) bt
#0  internal_error (gmsgid=0x15ee807 "in %s, at %s:%d") at
../../gcc/diagnostic.c:1337
#1  0x01266866 in fancy_abort (file=0x157ccd5 "../../gcc/emit-rtl.c",
line=1025, function=0x190cd98 "gen_reg_rtx") at ../../gcc/diagnostic.c:1405
#2  0x00945479 in gen_reg_rtx (mode=V2DImode) at ../../gcc/emit-rtl.c:1025
#3  0x00579f86 in gen_split_349 (curr_insn=0x325acf0, operands=0x1ff95c0) at
../../gcc/config/i386/sse.md:1129
#4  0x0076bb58 in split_8 (x1=0x3255ce4, insn=0x325acf0) at
../../gcc/config/i386/sse.md:1115
#5  0x00778c75 in split_insns (x1=0x3255ce4, insn=0x325acf0) at
../../gcc/config/i386/sse.md:13387
#6  0x0094b3e4 in try_split (pat=0x3255ce4, trial=0x325acf0, last=1) at
../../gcc/emit-rtl.c:3658
#7  0x00d4a502 in split_insn (insn=0x325acf0) at ../../gcc/recog.c:2887
#8  0x00d4a7c5 in split_all_insns () at ../../gcc/recog.c:2977
#9  0x00d4c34b in rest_of_handle_split_after_reload () at
../../gcc/recog.c:3913
#10 0x00d4c389 in (anonymous namespace)::pass_split_after_reload::execute
(this=0x50d0e190) at ../../gcc/recog.c:3942
#11 0x00d12144 in execute_one_pass (pass=0x50d0e190) at ../../gcc/passes.c:2344
#12 0x00d12495 in execute_pass_list_1 (pass=0x50d0e190) at
../../gcc/passes.c:2428
#13 0x00d124c5 in execute_pass_list_1 (pass=0x50d0e0d0) at
../../gcc/passes.c:2429
#14 0x00d124c5 in execute_pass_list_1 (pass=0x50d0d590) at
../../gcc/passes.c:2429
#15 0x00d12515 in execute_pass_list (fn=0x2b35bb8, pass=0x50d0b190) at
../../gcc/passes.c:2439
#16 0x008539ee in cgraph_node::expand (this=0x2d4b424) at
../../gcc/cgraphunit.c:1983
#17 0x00853fff in expand_all_functions () at ../../gcc/cgraphunit.c:2119
#18 0x00854c8b in symbol_table::compile (this=0x50e0b000) at
../../gcc/cgraphunit.c:2475
#19 0x00854ed1 in symbol_table::finalize_compilation_unit (this=0x50e0b000) at
../../gcc/cgraphunit.c:2565
#20 0x00e246cd in compile_file () at ../../gcc/toplev.c:490
#21 0x00e26f70 in do_compile () at ../../gcc/toplev.c:1998
#22 0x00e27332 in toplev::main (this=0xbfff94de, argc=140, argv=0xbfff9510) at
../../gcc/toplev.c:2132
#23 0x0124f80f in main (argc=140, argv=0xbfff9510) at ../../gcc/main.c:39
Current language:  auto; currently c++
(gdb) bt full
#0  internal_error (gmsgid=0x15ee807 "in %s, at %s:%d") at
../../gcc/diagnostic.c:1337
        ap = 0x0
        richloc = {
  static MAX_RANGES = <optimized out>, 
  static MAX_FIXIT_HINTS = <optimized out>, 
  m_num_ranges = 0, 
  m_ranges = {{
      m_loc = 33527040, 
      m_show_caret_p = 204
    }, {
      m_loc = 0, 
      m_show_caret_p = false
    }, {
      m_loc = 0, 
      m_show_caret_p = true
    }}, 
  m_column_override = 0, 
  m_have_expanded_location = 104, 
  m_expanded_location = {
    file = 0xd47953 "??\020\017????U???\030?x?\001\002??u2?E\b\017?", 
    line = 18, 
    column = 1356874188, 
    data = 0x0, 
    sysp = false
  }, 
  m_num_fixit_hints = 18, 
  m_fixit_hints = {0x50e041cc, 0x0}
}
        __FUNCTION__ = "internal_error"
#1  0x01266866 in fancy_abort (file=0x157ccd5 "../../gcc/emit-rtl.c",
line=1025, function=0x190cd98 "gen_reg_rtx") at ../../gcc/diagnostic.c:1405
No locals.
#2  0x00945479 in gen_reg_rtx (mode=V2DImode) at ../../gcc/emit-rtl.c:1025
        val = (rtx) 0xd479ef
        align = 128
        __FUNCTION__ = "gen_reg_rtx"
#3  0x00579f86 in gen_split_349 (curr_insn=0x325acf0, operands=0x1ff95c0) at
../../gcc/config/i386/sse.md:1129
        tmp = (rtx) 0x50e0e430
        _val = (rtx_insn *) 0x0
        __FUNCTION__ = "gen_split_349"
#4  0x0076bb58 in split_8 (x1=0x3255ce4, insn=0x325acf0) at
../../gcc/config/i386/sse.md:1115
        operands = (rtx * const) 0x1ff95c0
        x2 = (rtx) 0x3259dd0
        x3 = (rtx) 0x3259dc0
        x4 = (rtx) 0x32c22f0
        x5 = (rtx) 0x27c6018
        x6 = (rtx) 0x0
        x7 = (rtx) 0x3255ccc
        x8 = (rtx) 0x3254eb0
        x9 = (rtx) 0x32797e0
        x10 = (rtx) 0x0
#5  0x00778c75 in split_insns (x1=0x3255ce4, insn=0x325acf0) at
../../gcc/config/i386/sse.md:13387
        operands = (rtx * const) 0x1ff95c0
        x2 = (rtx) 0xbfff91d8
        x3 = (rtx) 0xbfff922b
        x4 = (rtx) 0x2d4b424
        x5 = (rtx) 0x3251a28
        x6 = (rtx) 0xbfff91c8
        x7 = (rtx) 0x27c0cdc
        x8 = (rtx) 0x325acf0
        x9 = (rtx) 0xc07a4e
        x10 = (rtx) 0xbfff91c8
        x11 = (rtx) 0x0
        x12 = (rtx) 0x3251a28
        x13 = (rtx) 0x95215c
        x14 = (rtx) 0xbfff91b8
        x15 = (rtx) 0x27c0cdc
        x16 = (rtx) 0x325ad14
        x17 = (rtx) 0x9521eb
#6  0x0094b3e4 in try_split (pat=0x3255ce4, trial=0x325acf0, last=1) at
../../gcc/emit-rtl.c:3658
        before = (rtx_insn *) 0x325aca8
        after = (rtx_insn *) 0x325ad14
        note = (rtx) 0x325aca8
        seq = (rtx_insn *) 0x0
        tem = (rtx_insn *) 0xbfff9248
        probability = -1
        insn_last = (rtx_insn *) 0x0
        insn = (rtx_insn *) 0x0
        njumps = 0
        call_insn = (rtx_insn *) 0x0
        __FUNCTION__ = "try_split"
#7  0x00d4a502 in split_insn (insn=0x325acf0) at ../../gcc/recog.c:2887
        first = (rtx_insn *) 0x325aca8
        last = (rtx_insn *) 0x3254eb0
        insn_set = (rtx) 0x3255ce4
        last_set = (rtx) 0x325acf0
        note = (rtx) 0x796dc3
#8  0x00d4a7c5 in split_all_insns () at ../../gcc/recog.c:2977
        set = (rtx) 0x3259dd0
        insn = (rtx_insn *) 0x325acf0
        next = (rtx_insn *) 0x325ad14
        finish = false
        blocks = (sbitmap) 0x3012620
        changed = true
        bb = (basic_block) 0x2dc79c0
#9  0x00d4c34b in rest_of_handle_split_after_reload () at
../../gcc/recog.c:3913
No locals.
#10 0x00d4c389 in (anonymous namespace)::pass_split_after_reload::execute
(this=0x50d0e190) at ../../gcc/recog.c:3942
No locals.
#11 0x00d12144 in execute_one_pass (pass=0x50d0e190) at ../../gcc/passes.c:2344
        todo_after = 0
        gate_status = true
        __FUNCTION__ = "execute_one_pass"
#12 0x00d12495 in execute_pass_list_1 (pass=0x50d0e190) at
../../gcc/passes.c:2428
        __FUNCTION__ = "execute_pass_list_1"
#13 0x00d124c5 in execute_pass_list_1 (pass=0x50d0e0d0) at
../../gcc/passes.c:2429
        __FUNCTION__ = "execute_pass_list_1"
#14 0x00d124c5 in execute_pass_list_1 (pass=0x50d0d590) at
../../gcc/passes.c:2429
        __FUNCTION__ = "execute_pass_list_1"
#15 0x00d12515 in execute_pass_list (fn=0x2b35bb8, pass=0x50d0b190) at
../../gcc/passes.c:2439
        __FUNCTION__ = "execute_pass_list"
#16 0x008539ee in cgraph_node::expand (this=0x2d4b424) at
../../gcc/cgraphunit.c:1983
        saved_loc = 217398336
        __FUNCTION__ = "expand"
#17 0x00853fff in expand_all_functions () at ../../gcc/cgraphunit.c:2119
        node = (cgraph_node *) 0x2d4b424
        order = (cgraph_node **) 0x50dd81c0
        expanded_func_count = 9
        profiled_func_count = 0
        order_pos = 84
        new_order_pos = 20
        i = 11
        __FUNCTION__ = "expand_all_functions"
#18 0x00854c8b in symbol_table::compile (this=0x50e0b000) at
../../gcc/cgraphunit.c:2475
        node = (symtab_node *) 0x0
        __FUNCTION__ = "compile"
#19 0x00854ed1 in symbol_table::finalize_compilation_unit (this=0x50e0b000) at
../../gcc/cgraphunit.c:2565
        cnode = (cgraph_node *) 0x0
#20 0x00e246cd in compile_file () at ../../gcc/toplev.c:490
        pkg_version = 0xe26f68
"??\020?????\r??\fj\002蘳????\020??\fj\n???????\020\017?\005G\033?\001\017????\fP??????\020??\fj\n?h?????\020???U???\004?E\020?E??}\f"
        ident_str = 0xbfff94a8 "????2s?"
#21 0x00e26f70 in do_compile () at ../../gcc/toplev.c:1998
        i = 1
#22 0x00e27332 in toplev::main (this=0xbfff94de, argc=140, argv=0xbfff9510) at
../../gcc/toplev.c:2132
No locals.
#23 0x0124f80f in main (argc=140, argv=0xbfff9510) at ../../gcc/main.c:39
        toplev = {
  m_use_TV_TOTAL = true, 
  m_init_signals = true
}
(gdb) call debug_rtx((rtx)0xd479ef)
(??? bad code 50307
)


Let me know if there's any other debugging commands I should try.

Latest version info:
$ ./xg++ -v
Using built-in specs.
COLLECT_GCC=./xg++
Target: i386-apple-darwin9.8.0
Configured with: ../configure --enable-languages=c,objc,c++,obj-c++
CC=/usr/local/bin/gcc CXX=/usr/local/bin/g++ OBJC=/usr/local/bin/gcc
OBJCXX=/usr/local/bin/g++
Thread model: posix
gcc version 7.0.0 20160627 (experimental) (GCC)